Newport FPM-8220, User Manual

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April 2018 29 FPM-8220
Command Syntax
The discussions below describe command syntax and structure. You need this information to
effectively write GPIB and USB control programs for the FPM-8220. The syntax of FPM-8220
commands follow the rules defined in the ANSI/IEEE-488 standard. ANSI/IEEE-488 uses
standard terminology. To clarify understanding, we use simpler terms for this manual.
Letters
Any command or query must contain all of the letters which are shown in upper case in the
command definition. Some of the device dependent commands include additional optional
letters shown in lower case in the command reference (Chapter 4). Upper/lower case does not
matter to the FPM-8220. It is just used in this manual to identify optional letters. The optional
letters must be in the correct sequence. Some examples of what works, and what does not:
Table 3.1 – Acceptable and Not Acceptable Spelling
Acceptable Not Acceptable
DISP DS
DISPlay or DISPLAY Displa or DISPL
White Space
“White space” is normally the space character (space bar). A single white space must separate a
command from its parameters or data. For example:
Table 3.2 – White Space
Acceptable Not Acceptable
WAVE 1234 WAVE1234
To enhance readability, one or more white spaces may be used before a comma, semicolon, or
terminator. Since the computer normally places the terminator at the end of each command string,
this simply means that an extra space character at the end of the command line is acceptable.
A query has no space between the mnemonic and the question mark. For example:
Table 3.3 – Query Formatting
Acceptable Not Acceptable
DISPLAY? DISPLAY ?